The present invention is related to trailers and more specifically to trailers utilized to carry a watercraft behind a towing vehicle.
Some difficulty has been experienced in loading and unloading of centerboard type sailboats to boat trailers. It has been found that the usually fragile hulls of such boats are easily damaged while being carried on a trailer and especially while being loaded and unloaded from the trailers. Centerboard sailboats generally have a vertically adjustable keel of considerable weight. When held on a trailer, such boats are ordinarily supported on opposite sides of the centerboard with the centerboard itself being held within the sailboat in a raised condition, or supported by a central roller or other provision on the boat trailer. Previous trailers utilize a stationary "form fitting" bunk arrangement that is preformed to conform to the hull shape of the particular boat to be carried. The rigidity of the bunks necessitates that the boat be held in a precise position on the trailer in order that its weight is evenly distributed thereon. Further, because the bunks are concave in shape with the forward and rearward ends pointing substantially upwardly, the trailer must be nearly completely submerged before the sailboat held thereby may be moved onto or off the trailer. Thus it is often necessary to provide an additional trailer tongue that enables extension of the distance between the trailer and towing vehicle, thereby allowing movement of the trailer into deeper water when necessary. If the trailer is to be loaded onto a submerged or nearly submerged trailer much difficulty is experienced in correctly positioning the boat over the submerged hull engaging members.
The present trailer includes longitudinal resilient bunks that are carried by a walking beam arrangement on the central supporting framework. The bunks are therefore free to flex in response to the weight of the boat thereon and to conform to the hull shape. However, when the boat is unloaded from the trailer, the resilient bunks will return to a normal relatively flat condition. When loading, the hull may engage the bunks and bend them slightly downwardly as the boat is pulled onto the trailer. Similarly, when unloading a sailboat, as the trailer is being backed into the water, the bunks will return to a relatively normal flat condition as buoyancy of the boat reduces the load applied thereto. The boat may float freely over the bunks once they return to a flat condition with no danger of the hull scraping against an upturned bunk end.